JP7730550B2 - String for Japanese bow, method for attaching string for Japanese bow, and string forming kit for Japanese bow - Google Patents

Description

The present invention relates to a string for a Japanese bow, a method for attaching a string for a Japanese bow, and a string-forming kit for a Japanese bow.

A bow is a weapon used to shoot arrows, but it is also used in martial arts and competitions such as Kyudo and archery. Bows can be broadly divided into Japanese bows and Western bows. Japanese bows are long bows used in Japanese Kyudo and archery.

The string is used to transfer the bow's energy to the arrow. A string is a strong cord or thread stretched across the bow. There are many types of string available on the market today.

In Japanese archery, the string is often called "tsuru" (string), and traditionally strings are made from hemp or ramie. The string has string loops on both ends for hanging on the bow, and the string is tensioned by hanging the string loops on convex bow loops (yuhazu) on both the top and bottom of the bow. Some players have a need to twist the ends of the straight string themselves to create a familiar string loop (twist) of their preferred shape and size.
Recently, strings made from synthetic resin fibers such as Kevlar, Zylon, and aramid fibers have become mainstream for Japanese bows. In particular, in recent years, strings for archery (Western bows), as will be described later, have been adapted for use with Japanese bows.

A Western-style bow string is made up of multiple strands (for example, 10 to 40 strands) of polyester fiber or other raw string threads bundled together (the string itself). The number of strands in a string is generally called the number of strands; for example, a 16-strand string would be written as 16str.
4, loops 92 (corresponding to string rings) are provided on both ends of the string body to be attached to the bow body, and the string is usually tensioned by attaching the loops 92 to limb tips provided on the top and bottom ends of the bow. Also, a center serving 93 is usually formed in approximately the center of the string body 91 for purposes such as protecting the area where the arrow is nocked.

The manufacturing process for bowstrings consists of, for example, a bundle string forming process, a loop forming process (loop forming method), and a center serving forming process. These manufacturing processes are well known and can be seen, for example, in the background art section of Japanese Patent Application No. 2021-19677 previously filed by the applicant, or in videos posted on video streaming sites (e.g., https://www.youtube.com/watch?v=83i6AV_Lnrs, https://www.youtube.com/watch?v=uEVHLoFAqG4).
A string making device (generally referred to as a string jig or jig) and a server (also referred to as a string server or serving tool) are used to manufacture strings.

As described in Patent Document 1 below, there is also a technology for reinforcing loop sections using heat-shrinkable plastic tubing. This document states that "a Western-style bowstring is made by wrapping a heat-shrinkable plastic tube around each loop section at both ends of the string body, which is formed by bundling the required number of strands (raw string threads), and then heat-shrinking the tube to secure the tube to the loop sections at both ends to form reinforcing loop sections." This "eliminates the need for the conventional process of winding reinforcing threads, and allows the loop section to be reinforced with the simple process of inserting the tube and heat-shrinking it, thereby making the string manufacturing process extremely efficient."

Utility Model Publication No. 49-874

However, when archery strings like those mentioned above were used for Japanese bows, there were issues with the durability of the loop. That is, repeated use could cause the reinforcing part or heat-shrinkable plastic tube to bend, exposing the string thread in the loop, and in some cases the string could break.

The present invention was made with the above in mind, and aims to provide a string for a Japanese bow that is highly durable and prevents the string threads from becoming exposed, a method for attaching the string to a Japanese bow, and a string-tying kit for a Japanese bow.

To solve the above problems, a Japanese bow string is developed, which comprises a string body made of multiple resin string threads, a reinforcing end formed by wrapping a reinforcing thread around the end of the string body, and a flexible braided sleeve that generally covers the tip of the reinforcing end. The reinforcing end bundles the multiple string threads that make up the string body with the reinforcing thread and reinforces the end of the string body. The braided sleeve also includes sleeve-shaped braided cords and the outer (sleeve-shaped) surface of a pararope, as described below.
It is also possible to form reinforcing ends at both ends of the string body, and cover each of the reinforcing ends with a braided sleeve.

This Japanese bow string, like conventional Japanese bow strings, can be attached to a Japanese bow by twisting the end of the string (the portion of the braided sleeve that covers the tip of the reinforcing end) to form a string loop, and then hanging the formed string loop on the Japanese bow sling. Note that strings for Japanese bows also include those that have a twist formed.
Furthermore, the tip of the reinforcing end of this Japanese bow string (the part that forms the string loop) is mostly covered with a flexible braided sleeve, which makes it less likely for the string thread to become exposed even with repeated use, resulting in excellent durability.
It is also possible to form reinforcing ends at both ends of the string body, and cover each of the reinforcing ends with a braided sleeve.

It can also be a string for a Japanese bow, with the length of the reinforced end being 15 to 55 cm and at least 3 cm longer than the length of the braided sleeve.

When shooting arrows frequently with a Japanese bow, the end of the string body can repeatedly hit the bow (for example, the bow tie), damaging the string body. This Japanese bow string protects the end of the string body with a reinforced end of a specified length, making the string less susceptible to damage and improving its durability. Because the length of the reinforced end is at least 3 cm longer than the length of the braided sleeve, the reinforced end protrudes at least 3 cm from the end of the braided sleeve.

The reinforcing thread can also be a string for a Japanese bow, with a thickness of 0.1 to 0.5 mm.

This Japanese bow string uses a relatively thin reinforcing thread, which makes the reinforcing section less likely to crack when bent, improving the durability of the resulting string loop (torsion). It also improves the fit between the string loop (torsion) and the bowstring. Furthermore, it keeps the weight of the string to a minimum, and prevents spoiling of the string's vibrations when shooting an arrow.

It can also be a string for a Japanese bow, in which the reinforcing thread contains high-strength polyethylene fibers.

This Japanese bow string has stronger reinforced ends, making it less susceptible to damage and improving durability.

It can also be used as a string for a Japanese bow, with the reinforcing thread containing Spectra fiber.

This Japanese bow string has increased strength at the reinforced end, making it even more resistant to damage and improving durability.

The braided sleeve can be used as a string for a Japanese bow made of synthetic resin fibers. The braided sleeve can also be used as a string for a Japanese bow made of a round braided material made of synthetic resin fibers.

This Japanese bow string features a braided sleeve that is lightweight, flexible, and strong, making it less likely for the string's raw threads to become exposed even with repeated use, improving durability.

The braided sleeve can also be used as a string for a Japanese bow, with a length of 10 to 30 cm.

This Japanese bow string protects the end of the string body with a braided sleeve of a specified length, making the string less susceptible to damage and improving its durability.

The above-mentioned problem can also be solved by a method for attaching a Japanese bow string to a Japanese bow, which involves forming a string loop in the portion of the braided sleeve that substantially covers the tip of the reinforcing end, and then attaching the string to the Japanese bow by hanging the formed string loop on the bow sling.

Japanese bow competitors have a need to be able to shape the string loop that attaches the string to the bowstring sling to their desired shape and size. This method of attaching a string for a Japanese bow can meet this need.

Furthermore, the above-mentioned problems can also be solved by a string-making kit for Japanese bows, which consists of a reinforcing string with a reinforcing end formed by winding a reinforcing thread around the end of a string body made of multiple resin string strands, and a braided sleeve that generally covers the reinforcing end of the reinforcing string.

This invention makes it possible to provide a string for a Japanese bow that is highly durable and prevents the string thread from becoming exposed, a method for attaching the string to a Japanese bow, and a string-making kit for a Japanese bow.

This is a diagram (photograph) illustrating a string for a Japanese bow. FIG. 10 is a partially enlarged view (photograph) illustrating the reinforced end portion and the braided sleeve. 10 is a partially enlarged view (photograph) illustrating the state in which a portion of the braided sleeve is twisted to form a string loop. FIG. 1 is a diagram (photograph) illustrating a string for a Western bow.

Below, we will explain examples of strings for Japanese bows using the figures. A string for a Japanese bow has a string body, a reinforcing end, and a braided sleeve. In Figure 1, a string loop (twist) is formed only on one end of the string for a Japanese bow.
Each component will be illustrated below, but the present invention and its components are not limited to the following description. First, the string body will be illustrated.

1. String Body The string body 2 is made up of multiple resin string threads 21 (sometimes also commonly referred to as strands). For example, the string threads 21 may be those used in archery strings. There are no particular restrictions on the material of the string threads 21 as long as they are made of resin, but for example, those made from polyethylene fiber, polyester fiber, or polyaramid fiber may be used. In this embodiment, the string threads 21 are made from high-density polyethylene fiber.

Several such string yarns 21 are bundled together to form the string body 2. In this embodiment, 16 string yarns 21 are bundled together to form a 16-strand string body 2.

2. Reinforced End The reinforced end 3 is configured by wrapping a reinforcing thread around the end of the string body 2. A reinforced end 3 is usually formed at each end of the string body 2. The reinforced end 3 is formed at the end of the string body 2; for example, in Figures 1 to 3, the reinforced end 3 is also present below the braided sleeve 4.

There are no particular restrictions on the material of the reinforcing thread wound around the end of the string body 2 to form the reinforcing end 3. For example, high-strength fibers such as high-strength polyethylene fiber, polyester fiber, nylon fiber, and aramid fiber can be used. It is particularly preferable that the reinforcing thread contain high-strength polyethylene fiber.

High-strength polyethylene fibers are typically produced using a process known as the gel-spinning process, whereby gel-spun ultra-high molecular weight polyethylene is turned into fibers.

Examples of such high-strength polyethylene fibers include "Dyneema" (trade name) manufactured by Toyobo Co., Ltd., "Dyneema" (trade name) manufactured by DSM, and "Spectra" (trade name) manufactured by Honeywell. Of these, it is preferable to use "Spectra" (hereinafter referred to as "Spectra fiber").

Such high-strength polyethylene fibers offer excellent knife-resistant properties, as well as water-repellent, weather-resistant, antibacterial, and flexibility, as well as strong resistance to ultraviolet rays and chemicals. Incidentally, Spectra fiber is 8 to 10 times stronger than steel and over 1.4 times stronger than aramid fiber, and its specific gravity is extremely light, at approximately 0.97, where water is 1. It is also resistant to seawater, hydraulic fluid, kerosene, heating oil, gasoline, toluene, glacial vinegar, hydrochloric acid, bleach, and more, and bacteria are less likely to grow in it than in cotton or aramid. Furthermore, its low moisture absorption means it does not absorb sweat or odors, and odors are less likely to remain in the fiber itself. It also has excellent resistance to flex fatigue and abrasion.

The thickness of the reinforcing yarn made from such fibers is preferably relatively thin, ranging from 0.1 to 0.5 mm. The thickness of the reinforcing yarn is more preferably 0.15 to 0.4 mm, and even more preferably 0.2 to 0.25 mm. Converted to inches, the thickness of the reinforcing yarn is preferably relatively thin, ranging from 0.0039 to 0.0197 inches. The thickness of the reinforcing yarn is more preferably 0.0059 to 0.0157 inches, and even more preferably 0.0079 to 0.0098 inches.

It is also preferable that the reinforcing thread contain a resin component or be coated with a resin component. This improves the frictional force of the reinforcing thread. Furthermore, when winding the reinforcing thread around the string body, there is no need to use any adhesive to bond the two together.

In this embodiment, the reinforcing thread used was Power Grip Serving (0.009) manufactured by BCY Bowstring, which is made of Spectra fiber and nylon fiber and has a resin coating to improve friction, and has a wire diameter of 0.009 in (approximately 0.228 mm).

The reinforcing thread is wound around the end of the string body 2 to form the reinforcing end 3. There are no particular restrictions on the method for winding the reinforcing thread around the end of the string body 2, but the following method, for example, can be used.
First, the string yarn is wrapped around the pins of the stringing device multiple times (half the desired number of strands) to form a ring-shaped assembly. Next, a predetermined length of reinforcing yarn is wound tightly around both ends of this ring-shaped assembly using a winding tool such as a server. End treatment can be performed as desired. Finally, since there are usually areas at the ends of the ring-shaped assembly where the reinforcing yarn cannot be wound, these areas are cut off. In this way, the reinforcing end portions 3 can be formed at the ends of the string body 2.
Alternatively, the following method is also possible. First, the raw string yarn is wound around the pins of the stringing device multiple times (the desired number of strands) to form a ring-shaped assembly. Next, a winding tool such as a server is used to tightly wind a predetermined length of reinforcing yarn around a predetermined location on this ring-shaped assembly. The reinforcing yarn is then cut approximately in the center of the portion around which it is wound, thereby forming the reinforcing end portions 3 at both ends of the string body 2. If desired, the cut portions can be treated (by burning, for example).

The length 3L of the reinforcing end 3 (see Figure 2) is preferably 15 to 55 cm. The reinforcing end 3 may be of different lengths at both ends of the string body. Furthermore, while the reinforcing end 3 is formed at the end of the string body 2, it is preferable that it be formed all the way to the end of the string body 2 or near the end.
Furthermore, since the tip portion (left end in FIG. 2 ) of the reinforcing end portion 3 is mostly covered by the braided sleeve 4 described below, it is preferable to make the length of the braided sleeve 4 shorter than the length of the reinforcing end portion 3 (the length of the reinforcing end portion 3 is longer than the length of the braided sleeve 4 so that there is a protrusion 3P of the reinforcing end portion 3). Specifically, it is preferable to make the length of the reinforcing end portion 3 longer than the length of the braided sleeve 4 by 3 cm or more (the protrusion 3P of the reinforcing end portion 3 is 3 cm or more), and more preferably make it longer by 5 cm or more (the protrusion 3P of the reinforcing end portion 3 is 5 cm or more).
A string body 2 with a reinforcing end portion 3 formed thereon is called a reinforcing string (described later).

3. Braided Sleeve The braided sleeve 4 is flexible and is placed over the tip of the reinforcing end 3 (the end opposite the end located toward the center of the string body 2), thereby generally covering the tip of the reinforcing end 3. The braided sleeve 4 is a sleeve-shaped (cylindrical or tubular) knitted or braided fabric made of fibers. Braided sleeves also include sleeve-shaped braided cords and the outer (sleeve-shaped) surface of pararopes, which will be described later.

The braided sleeve 4 is preferably made of synthetic resin fibers. The synthetic resin fibers are not particularly limited, but examples thereof include polyester fibers, nylon fibers, and polyethylene fibers. The braided sleeve is preferably a braid made of synthetic resin fibers, and is particularly preferably a round braid made of synthetic resin fibers. The round braid may be a tubular braid in which two groups of threads run spirally in opposite directions and intersect with each other.
The braided sleeve 4 made of such a round braid has no fabric edges on the longitudinal side and is excellent in flexibility, stretchability, and conformability. For example, it has the excellent characteristics of becoming thinner when pulled from both ends in the longitudinal direction, and becoming thicker when compressed from both ends.

For example, the outer fabric of paracord (also known as parachute cord) may be used as the braided sleeve 4. Paracord is composed of multiple inner cores and a sleeve-like braided outer fabric that covers them. Therefore, the outer fabric of paracord from which the multiple inner cores have been removed can be used as a braided sleeve (a round braid made from synthetic resin fibers).

The length 4L of the braided sleeve 4 is preferably 10 to 30 cm. It is also preferably shorter than the length of the reinforced end portion 3 described above. In this embodiment, a braided sleeve approximately 19 cm in length was used.

The braided sleeve 4 may be left covering the reinforcing end 3, for example by placing it over the reinforcing end 3, or it may be fixed in position relative to the reinforcing end 3. For example, a portion of the braided sleeve 4 (e.g., both ends or one end) may be fixed in position to the reinforcing end 3 by gluing or the like.

It should be noted that the kit can also be sold without the braided sleeve 4 covering the reinforcing end 3. For example, it could be a string-making kit for a Japanese bow, consisting of a reinforcing string having a reinforcing end 3 formed by wrapping a reinforcing thread around the end of a string body 2 made of multiple resin string threads 21, and a braided sleeve 4 that generally covers the reinforcing end 3 of the reinforcing string. A purchaser of this string-making kit for a Japanese bow would place the braided sleeve 4 over the reinforcing end 3 of the reinforcing string, thereby covering the reinforcing end 3 with the braided sleeve 4.

4. Method of Attaching to a Japanese Bow As a method of attaching a Japanese bow string 1 having such a configuration to a Japanese bow, for example, as shown in Figure 3, the portion of the braided sleeve 4 that substantially covers the tip of the reinforcing end portion 3 can be twisted to form a string loop 5, and the formed string loop 5 can be placed on the bow sling of the Japanese bow to attach the string to the Japanese bow.

The present invention has been described above with reference to specific embodiments, but the present invention is not limited to the above embodiments, and various changes and modifications may be made by those skilled in the art without departing from the scope of the claims attached to this application.

1. Strings for Japanese bows

2. String body
21 String raw yarn

3 Reinforced end
3L Reinforced end length
3P Reinforcement part protrusion

4 Braided sleeves
4L Braided sleeve length

5. String Ring (Torsion)

9. Western-style bow strings
91 String body
92 Loop section
93 Center Serving

Claims (7)

a string body made of a plurality of resin string threads;
a reinforcing end portion formed by winding a reinforcing thread around the end portion of the string body;
a flexible braided sleeve that generally covers the tip of the reinforcing end ,
The length of the reinforced end portion is 15 to 55 cm and is at least 3 cm longer than the length of the braided sleeve;
The protrusion of the reinforced end portion from the end of the braided sleeve is 3 cm or more,
The reinforcing yarn is
High-strength polyethylene fibers having a thickness of 0.1 to 0.5 mm are included.
String for Japanese bow.
The high strength polyethylene fiber is Spectra fiber.
The string for a Japanese bow according to claim 1 .
The braided sleeve is made of synthetic resin fibers.
3. The string for a Japanese bow according to claim 1 or 2 .
The braided sleeve is a round braid made of synthetic resin fibers.
The string for a Japanese bow according to any one of claims 1 to 3 .
The length of the braided sleeve is 10 to 30 cm.
The string for a Japanese bow according to any one of claims 1 to 4 .
A method for attaching the Japanese bow string according to any one of claims 1 to 5 to a Japanese bow, comprising:
A string loop is formed in a portion of the braided sleeve that substantially covers the tip of the reinforced end portion,
The string loop is then attached to the bow sling and the string is attached to the bow.
How to attach a string for a Japanese bow.
A string forming kit for forming the Japanese bow string according to any one of claims 1 to 5,
a reinforcing string having a reinforcing end portion formed by winding a reinforcing thread around an end portion of a string body made of a plurality of resin string threads;
a braided sleeve that generally covers the reinforced end of the reinforced string ;
The length of the reinforced end portion is
15 to 55 cm, and at least 3 cm longer than the length of the braided sleeve,
The reinforcing yarn is
High-strength polyethylene fibers having a thickness of 0.1 to 0.5 mm are included.
String forming kit for Japanese bows.